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D Wang CR Stockard L Harkins P Lott C Salih K Yuan 《Biotechnic & histochemistry》2013,88(3-4):179-189
Angiogenesis, or neovascularization, is known to play an important role in the neoplastic progression leading to metastasis. CD31 or Factor VIII-related antigen (F VIII RAg) immunohistochemistry is widely used in experimental studies for quantifying tumor neovascularization in immunocompromised animal models implanted with transformed human cell lines. Quantification, however, can be affected by variations in the methodology used to measure vascularization including antibody selection, antigen retrieval (AR) pretreatment, and evaluation techniques. To examine this further, we investigated the microvessel density (MVD) and the intensity of microvascular staining among five different human tumor xenografts and a mouse syngeneic tumor using anti-CD31 and F VIII RAg immunohistochemical staining. Different AR methods also were evaluated. Maximal retrieval of CD31 was achieved using 0.5 M Tris (pH 10) buffer, while maximum retrieval of F VIII RAg was achieved using 0.05% pepsin treatment of tissue sections. For each optimized retrieval condition, anti-CD31 highlighted small vessels better than F VIII RAg. Furthermore, the MVD of CD31 was significantly greater than that of F VIII RAg decorated vessels (p<0.001). The choice of antibody and AR method has a significant affect on immunohistochemical findings when studying angiogenesis. One also must use caution when comparing studies in the literature that use different techniques and reagents. 相似文献
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Chris CR Smith Lisa K Snowberg J Gregory Caporaso Rob Knight Daniel I Bolnick 《The ISME journal》2015,9(11):2515-2526
To explain differences in gut microbial communities we must determine how processes regulating microbial community assembly (colonization, persistence) differ among hosts and affect microbiota composition. We surveyed the gut microbiota of threespine stickleback (Gasterosteus aculeatus) from 10 geographically clustered populations and sequenced environmental samples to track potential colonizing microbes and quantify the effects of host environment and genotype. Gut microbiota composition and diversity varied among populations. These among-population differences were associated with multiple covarying ecological variables: habitat type (lake, stream, estuary), lake geomorphology and food- (but not water-) associated microbiota. Fish genotype also covaried with gut microbiota composition; more genetically divergent populations exhibited more divergent gut microbiota. Our results suggest that population level differences in stickleback gut microbiota may depend more on internal sorting processes (host genotype) than on colonization processes (transient environmental effects). 相似文献
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Schilders G Raijmakers R Malmegrim KC Vande Walle L Saelens X Vree Egberts W van Venrooij WJ Vandenabeele P Pruijn GJ 《Arthritis research & therapy》2007,9(1):R12
Recent studies have implicated the dying cell as a potential reservoir of modified autoantigens that might initiate and drive
systemic autoimmunity in susceptible hosts. A number of subunits of the exosome, a complex of 3'→5' exoribonucleases that
functions in a variety of cellular processes, are recognized by the so-called anti-PM/Scl autoantibodies, found predominantly
in patients suffering from an overlap syndrome of myositis and scleroderma. Here we show that one of these subunits, PM/Scl-75,
is cleaved during apoptosis. PM/Scl-75 cleavage is inhibited by several different caspase inhibitors. The analysis of PM/Scl-75
cleavage by recombinant caspase proteins shows that PM/Scl-75 is efficiently cleaved by caspase-1, to a smaller extent by
caspase-8, and relatively inefficiently by caspase-3 and caspase-7. Cleavage of the PM/Scl-75 protein occurs in the C-terminal
part of the protein at Asp369 (IILD369↓G), and at least a fraction of the resulting N-terminal fragments of PM/Scl-75 remains associated with the exosome. Finally,
the implications of PM/Scl-75 cleavage for exosome function and the generation of anti-PM/Scl-75 autoantibodies are discussed. 相似文献
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Tumor necrosis factor alpha (TNFα) activates the nuclear factor-kappaB (NF-κB) pathway in various cell types, leading to expression
of cell survival and inflammatory proteins. One mechanism of cell survival brought about by NF-κB is the inhibition of Activator
Protein-1 (AP-1), which when activated, could lead to cell death. However, TNFα can also induce the AP-1 pathway, and the
mechanisms by which these two pathways are regulated in response to TNFα are poorly understood. We proposed that Inhibitor
of κB Kinase gamma (IKKγ) (which is also known as NF-κB essential modulator, NEMO) plays a key role in integrating and coordinating
these two pathways. Our results showed that IKKγ activates the AP-1 pathway, via a mechanism that is dependent on the first
leucine zipper (LZ) domain of IKKγ, by interacting with two proteins of the AP-1 complex, c-Jun and c-Fos, and changing the
phosphorylation status of c-Jun. Even though IKKγ is required for the activation of NF-κB, we found that it reduced the activity
of NF-κB when it was overexpressed. In summary, we demonstrated that transfected IKKγ, while inhibiting the NF-κB pathway,
directly interacts with the AP-1 proteins and activates the AP-1 pathway independent of its effects on NF-κB. Our results
indicate that IKKγ regulates TNFα signaling by coordinating cell responses mediated by the AP-1 and NF-κB pathways.
A. S. Shifera and J. M. Friedman contributed equally to this article.
Marshall S. Horwitz—Deceased: This article is dedicated to his loving memory. 相似文献
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S Devereux T G Selassie G Vaughan Hudson B Vaughan Hudson D C Linch 《BMJ (Clinical research ed.)》1990,301(6760):1077-1080
OBJECTIVE--To determine the incidence of and risk factors for the development of secondary acute leukaemia and myelodysplasia in patients treated in British National Lymphoma Investigation''s studies of Hodgkin''s disease since 1970. PATIENTS--2676 Patients entered into Hodgkin''s disease studies between February 1970 and November 1986. Data accrued up to November 1988 were analysed, ensuring a minimum follow up period of two years. DESIGN--Retrospective analysis of multicentre trial data by case-control and life table methods. RESULTS--17 Cases of secondary leukaemia were recorded in this group of 2676 patients, giving an overall risk at 15 years of 1.7%. The risks of leukaemia after chemotherapy alone and chemotherapy with radiotherapy were not significantly different. The risk of leukaemia increased sharply with the amount of treatment given as measured by the number of attempts at treatment. The 15 year risks of leukaemia were 0.2%, 2.3%, and 8.1% for patients receiving one, two, or three or more attempts at treatment. The highest risk, 22.8% at 15 years, was observed in patients treated with lomustine (CCNU), and a case-control study suggested that this was an independent risk factor. The risk of secondary leukaemia was largely related to the overall quantity of treatment, although exposure to lomustine seemed to be an important risk factor. Treatment with both drugs and radiation was not more leukaemogenic than treatment with drugs alone. The greatest risk of secondary leukaemia was seen in multiply treated patients who were unlikely to be cured of Hodgkin''s disease. CONCLUSIONS--Avoidance of secondary leukaemia should be a minor factor in the choice of treatment for Hodgkin''s disease. 相似文献
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CR Taylor 《Biotechnic & histochemistry》2014,89(6):419-423
The traditional microscope, together with the “routine” hematoxylin and eosin (H & E) stain, remains the “gold standard” for diagnosis of cancer and other diseases; remarkably, it and the majority of associated biological stains are more than 150 years old. Immunohistochemistry has added to the repertoire of “stains” available. Because of the need for specific identification and even measurement of “biomarkers,” immunohistochemistry has increased the demand for consistency of performance and interpretation of staining results. Rapid advances in the capabilities of digital imaging hardware and software now offer a realistic route to improved reproducibility, accuracy and quantification by utilizing whole slide digital images for diagnosis, education and research. There also are potential efficiencies in work flow and the promise of powerful new analytical methods; however, there also are challenges with respect to validation of the quality and fidelity of digital images, including the standard H & E stain, so that diagnostic performance by pathologists is not compromised when they rely on whole slide images instead of traditional stained tissues on glass slides. 相似文献
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Pedro LC Pinheiro João CR Cardoso Ana S Gomes Juan Fuentes Deborah M Power Adelino VM Canário 《BMC evolutionary biology》2010,10(1):373